1. Field of the Invention
The invention relates to a directly driven coiler for winding rolled strip into coils in accordance with the preamble of claim 1.
2. Description of the Related Art
Such directly driven coilers have become known, for example, through DE-PS 17 52 185 or DE-OS 39 39 119. In these coilers, the relative axial displacement between the coiler shaft and the plunger connected to the segments is effected through mechanical adjustment drives. These adjustment drives are bent lever drives or spring assemblies and spacer elements which can only be actuated when the coiler stands still. Any retightening during the coiling process is not possible in these adjustment drives.
Piston-cylinder units have become known through DE-OS 35 02 452 by means of which it is possible to tighten and release the spring assemblies which serve as adjustment drives and have the above-described disadvantages.
EP-PS 0 004 854 also discloses a piston-cylinder unit which serves directly as an adjustment drive for spreading and despreading the coiler. However, these two coilers provided with piston/cylinder units are not directly driven coilers of the generic type mentioned above, but indirectly driven coilers in which the drive motor is arranged next to the coiler shaft.
The coiler according to EP-OS 0 004 854 does have central rotary feeds, so that, for example, retightening during the coiling procedure is possible, however, if the drive motor for the coiler were to be flanged directly to the coiler shaft, this would result in difficulties in connection with the pressure medium supply because, as a rule, only solid motor shafts are being used, so that the pressure medium could not be conducted to the piston/cylinder unit from the end of the shaft where the pressure medium is fed in. However, if the pressure medium supply is to be placed through the motor shaft, the magnetic effect in the motor could magnetize metal particles in the pressure medium and could possibly lead to clogging of the supply lines. In addition, complicated flexible pressure medium connections would have to be provided in order to bridge any lateral offsets or axial displacements between the drive unit and the coiler shaft.
Rotary feeds have become known through DE-PS 38 06 931 through which the pressure medium can be conveyed radially into a shaft; these rotary feeds have very narrow manufacturing tolerances for an optimum operation, wherein these very narrow manufacturing tolerances exclude a use in difficult conditions as they prevail in rolling mills. In addition, these rotary feeds can only be used up to structural sizes with a maximum 18 mm diameter at the annular gap. Also for this reason, a use in rolling mill plants, for example, rolling mill coilers, where significantly greater diameters are used, could not take place.